Well, if you don't have consent, you cannot track that, correct?
So, you could / should for sure not track analytics opt outs 😂
OneTrust has its own dashboard you can look at. Unfortunately no API to pull the data out.
Another option I have set up for a client: set up a proxy that you can send custom analytics calls through, that strips all outgoing and incoming cookies. At the same time, the IP is obfuscated, so you end up having a fully anonymized, cookieless AA consent tracking.
Problem: you cannot load an analytics library and will have to forge your own tracking requests...